Spiral concentrators



July 30, 1963 F. A. CLOSE SPIRAL CONCENTRATORS Filed Aug. 51, 1960United States Patent 3,099,621 SPIRAL CONCENTRATORS Frank ArchibaldClose, Sydney, New South Wales, Australia, assignor to Wyong MineralsLimited, Sydney, New South Wales, Australia Filed Aug. 31, 1960, Ser.No. 53,253 Claims. (Cl. 209-459) This invention relates to spiralconcentrators for the separation of minerals, particularly sands.

The invention has been specially devised to improve the construction ofsuch spiral concentrators and eliminate the use of wash water which isin many mining situations difiicult or costly to provide, and alsorequires to be clean or to be filtered and involves the use ofadditional apparatus.

A further advantage resides in compactness whereby it is possible withone spiral of the special form, later herein described, to achieve thesame effect as three sets of spirals together with their necessary pumpsand connections for recirculation. Also, the amount of power required isreduced because the need for pumping is no longer required, and thecapital cost of the spiral installation itself is reduced to less thanhalf that formerly necessary. \Other advantages will be apparent fromthe following description.

According to this invention the spiral is characterised by a series ofparallel launders formed therein so that in one pass through, thematerial is concentrated through three or more stages, providing a highgrade concentrate product, a middling product, a sand tailing product,and a water tailing product.

In a typical example of the invention the spiral is formed in three orfour parallel launders, which reduce in width from the first one, whichis the primary one to the last and smallest one which is the tertiarylaunder for the concentrates and the upper levels of said launders mayslope downwards toward the outside launder on the inside of the spiraland the wall between them may be progressively reduced in height.

In the Walls between the launders at :a series of locations there aresplitting channels arranged and lead-in shapings at the entries thereof.Such splitting channels lead from the primary launder to the secondlaunder or launders and from same to the tertiary launder.

There may be a cover or shield provided over the top portion of thespiral particularly in regard to the primary launder or such shield mayextend partly thereover on the inside.

There may be water take-oils arranged at locations in the turns of thespiral particularly in the primary launder.

A movable splitter of any suitable form may be arranged at the bottom ofthe third channel to split the material into a concentrate and amiddling.

In order to describe the invention more fully, reference will now bemade to the accompanying drawings, wherein:

FIGURE 1 is a somewhat schematic "face elevation of a spiralconcentrator according to the invention, and

FIGURE 2 is an enlarged plan view of a portion of such spiralconcentrator, while FIGURE 3 is a cross section on line 3-3 of FIG- URE2.

The spiral concentrator consists of a series of convolutions generallyindicated by the reference 4 leading from a top supply hopper 5 or othersource to a bottom discharge point.

The spinal 4 is formed across in four parallel launders 6, 7, 8 and 9 inwhich launder 6 is the primary one and on the outside and of the largestsize while the two 3,099,621 Patented July 30, 1963 ice launders 7 and 8of smaller size or cross section are for the sands and form thesecondary launders While the launder 9 which is on the inside of thespiral, is the tertiary launder for the minerals or concentrates. Theselaunders 6-9 are separated by divisional walls 10 and are arranged atlevels sloping to the inside of the spiral and the said wallprogressively reduce in height.

In these divisional walls there are a series of splitting channels 11which may be arranged at intervals throughout the spiral 4 ofapproximately 10 inches apart, although not limited to any specialdistance.

The primary launder 6 has a lip .13 extended over the top on the outsideedge and there are one or more water take oifs 14-,at suitable intervalsapart.

In use the bulk material is fed to the top of the spiral concentrator 4:from the .hopper 5 into the primary launder 6 together with wash waterand a centrifugal eflect is set up as the material flows down and thebulk of the wash 'water With lighter particles passes along the saidlaunder 6 while the heavier particles including the sands andconcentrates are projected outwardly and directed through the channels11 by the flared ends 12, and so the stands separate out into secondarylaunders 7 and 8 while the heaviest particles forming the concentratesgravitate into the tertiary launder 9- and so discharge therefrom at thebottom end of the spiral 4 and are collected in any suitable mannerwhile the sands discharge to waste. The water may be collected forre-use in places where it is scarce.

In the above described spiral concentrator, by reason of the arrangedlaunders and their fixed splitting channels there is provided in thesecondary and tertiary launders an effect equivalent to that provided bywash Water and the material flows freely without tendency to blockages.

I claim:

1. A concentrator for the separation of minerals comprising a spiralchannel having its entire outer edge positioned at a level higher thanits respective inner edge, said spiral channel having a plurality ofparallel launders formed therein throughout the length thereof, saidlaunders progressively decreasing in size from the outer edge to theinner edge of said spiral channel, the wall separating each of saidadjacent pairs of launders having a plurality of inwardly directedchannels formed therein, the path of flow of said channels being fromthe larger to the smaller of said pair of launders, said channels beingintermittently distributed through the Walls separating each pair oflaunders throughout the length of said spiral channel, whereby whenmaterial flows downwardly through said spiral channel, the particles ofthe material will be separated into particles of varying weight with theparticles of heaviest weight in the innermost launder and the particlesof lightest weight in the outermost.

2. A concentrator as defined in claim 1 wherein the walls betweenadjacent pairs of said launders progressively increase in height fromthe inner pair to the outer pair of launders.

3. A concentrator as defined in claim 2 further including a watertake-oil outlet arranged at intervals throughout the length of thespiral channel and communicating with the outer launder of said channel.

4. A concentrator for the separating of minerals comprising a spiralchannel, said spiral channel including a primary launder at the outeredge thereof, secondary launders parallel and adjacent to said primarylaunder, and a tertiary launder at the inner edge of said spiral channelparallel and adjacent to said secondary launders, said laundersprogressively decreasing in size from said primary launder to saidtertiary launder, the walls be- 3,099,621 3 4 tween adjacent laundersprogressively decreasing in height launder is substantiallysemi-circular in cross-section and from the primary launder to thetertiary launder, each has its inner edge lower than its respectiveouter edge. of he walls between adjacent launders provided with aninwardly directed channel spaced at intervals therein, References Cltedm the file of thls patent whereby the downstream flow of materialadjacent the 5 UNITED STATES PATENTS inner surface of he primary andsecondary lannders is 2,431,559 Humphreys Nov. 25, 1947 directed to flowinto the adjacent smaller launder through 2,43 1,5 0 Humphreys Nov. 25,1947 said channels. 2,615,572 Hodge Oct. 28, 1952 5. A concentrator asdefined in claim 4 wherein each 2,700,469 Humphreys Jan. 25, 1955

1. A CONCENTRATOR FOR THE SEPARATION OF MINERALS COMPRISING A SPIRALCHANNEL HAVING ITS ENTIRE OUTER EDGE POSITIONED AT A LEVEL HIGHER THANITS RESPECTIVE INNER EDGE, SAID SPIRAL CHANNEL HAVING A PLURALITY OFPARALLEL LAUNDERS FORMED THEREIN THROUGHOUT THE LENGTH THEREOF, SAIDLAUNDERS PROGRESSIVELY DECREASING IN SIZE FROM THE OUTER EDGE TO THEINNER EDGE OF SAID SPIRAL CHANNEL, THE WALL SEPARATING EACH OF SAIDADJACENT PAIRS OF LAUNDERS HAVING A PLURALITY OF INWARDLY DIRECTEDCHANNELS FORMED THEREIN, THE PATH OF FLOW OF SAID CHANNELS BEING FROMTHE LARGER TO THE SMALLER OF SAID PAIR OF LAUNDERS, SAID CHANNELS BEINGINTERMITTENTLY DISTRIBUTED THROUGH THE WALLS SEPARATING EACH PAIR OFSAUNDERS THROUGHOUT THE LENGTH OF SAID SPIRAL CHANNEL, WHEREBY WHENMATERIAL FLOWS DOWNWARDLY THROUGH SAID SPIRAL CHANNEL, THE PARTICLES OFTHE MATERIAL WILL BE SEPARATED INTO PARTICLES OF VARYING WEIGHT WITH THEPARTICLES OF HEAVIEST WEIGHT IN THE INNERMOST LAUNDER AND THE PARTICLESOF LIGHTEST WEIGHT IN OUTERMOST.